Don't use a whip - use a 'whip-dagger', from Arms and Equipment.
Go for disarming/tripping when he's forced into physical combat, whips generally aren't particularly good for actual combat.
He absolutely has to have a group of elite bodyguards.
I recommend a spellcaster of some type, because that will keep him out of melee combat, which, realistically speaking, with a whip, he's not going to be great at.
But, more importantly, more information.
What level(s)? What books are available? Anything other than a whip-user to define this character?